The present invention relates to lateral expansion devices with at least two substantially axially parallel blade surfaces that expand from a central axis such that at least an orifice is increased in effective diameter.
It has been known through a very long history of medical expanders and speculums that moving three to five closely aligned parallel blades outwardly can create a valuable orifice expansion effect. Two main classes of these devices emerge from the art. A first class, the more difficult mechanically, maintains the longitudinal axes of the blades in substantially parallel relationship as they outwardly expand against the orifice edges. A second class, with an action typical of the dual bladed vaginal speculum, maintains the base of the blade in a substantially fixed position while the distal ends move equidistant from a central axis. The prior art classes are found in the following U.S. Pat. Nos.: 241,036, 242,443, 540,835, 972,983, 1,244,751, 1,427,653, 1,827,497, 2,083,573, 2,137,121, 2,485,939, 3,517,128, 3,565,061, 3,667,474, 3,688,773, 3,759,263, 4,130,113, and 5,377,667. Vaginal speculums typical of the current state of the art are found in the Cooper Surgical Winter 1996 catalog of CooperSurgical Inc. at page 18 and in the Cooper Surgical Spring 1997catalog of CooperSurgical Inc. at page 29. Two bladed lateral wall retractors typical of the current state of the art are shown in the Cooper Surgical Winter 1996 catalog of CooperSurgical Inc. at page 29.
It is a special object of the present invention to address the function of a combined application of a vaginal speculum and a lateral wall retractor shown Cooper Surgical Winter 1996 catalog of CooperSurgical Inc. at the top illustrations of page 18. In that set of illustrations, it is clear that the combined action of the speculum and retractor present a far more effective view of the cervix. The confused and unstable mass of equipment used to achieve that effect is a disadvantage to the skilled examiner. It is an object of the present invention to at least effect the function of the combined speculum/retractor apparatus of Cooper Surgical Winter 1996 catalog of CooperSurgical Inc. at page 18. It is further an object of the present invention to present an effective new expansion motion for at least two lateral expansion blades whose axes remain substantially parallel during a first expansion motion.
The present invention comprises a lateral expansion device with a novel relative lateral motion of at least two to four blades. In a four blade embodiment, four blades are arranged initially such that their effective forcing planes are substantially axially and facially parallel to each other in a closed position, although maintaining substantially axially parallel positions throughout a first lateral expansion motion. In that embodiment, two of the blades, a top and bottom blade, are at an initial, closed position axially bracket two other blades, a left and right blade, which are adapted to expand substantially axially directly opposite each other in a straight path to a ultimate positions left and right of their initial positions, respectively.
The lateral motion of the left and right blades is substantially similar to the motion of the blades of the lateral retractor shown and described, as is well known in the art, in the Cooper Surgical Winter 1996 catalog of CooperSurgical Inc. at page 18. Lateral motion forcing means for the present invention includes, as an example, the forcep-type, ratcheting position-locking handles shown and well known to the art for the lateral wall retractor of Cooper Surgical Winter 1996 catalog of CooperSurgical Inc. at page 18.
One form of the four blade embodiment includes four pivotally interlocking base plates, one base plate per blade, adapted such that each blade is secured at one end substantially perpendicular to its own base plate. The following is a description of the motion of the blades from an initial, closed position to a furthermost expanded position. When viewed along an axis from the base plate attachment of the blades outward in the direction of the longitudinal axis of the blades, activation of the lateral motion forcing means forces the forcing plane of the top blade into an angularly smooth sweeping motion upward and to the right with respect to a lateral left hand motion of the forcing plane of the left blade, such that the top blade, in a first portion of the first lateral expansion motion, remains at least partly facially relatively close to and in front of the forcing plane of the left blade. Thus, the left blade moves laterally to the left while the top blade slides upward and to the right, maintaining a relatively continuously increasing force plane comprising the left facing left blade and the upwardly rotating top blade. In a second portion of the first lateral expansion motion, the left blade completes its path to furthest left hand position and the top blade rotates and upwardly moves outward in a relatively longer path as compared to the path of the left blade, such that the preferred final position of the top blade is substantially above and perpendicular the position of the left blade. The motions of the right blade and the bottom blade are opposite to but otherwise identical with those of the left blade and the top blade, respectively, such that in a furthest position away from the initial position, the right and left hand blades are facially substantially parallel and the top and bottom blades are facially substantially parallel.
In summary, the combined action of a left/top blade from the closed position to a furthermost lateral expansion position first develops a continuous combined force plane which lifts an upper portion of an orifice away from the left direction expansion of the left blade and finally results in a orifice opening expanded equally from an original small axis. Such an action, in the four blade embodiment, accomplishes the function of the combined vaginal speculum and lateral wall retractor currently required in the art for complete cervix exposure as shown in the upper illustration of the Cooper Surgical Winter 1996 catalog of CooperSurgical Inc. at page 18.
It should be understood that the blade of the present invention defines a physical piece of material and may comprise one or more rods or solid or perforated plates, such that the force applied to the lateral motion forcing means is translated into a lateral expansion of the blade as at least a part of an imaginary cross sectional forcing plane. The forcing plane is that widest face of an imaginary blade which would still accomplish the objects of the invention. The longitudinal axis of the blade is substantially the lateral cross section center of the blade. Thus, the blades of the present invention may comprise blades which are not facially opposite each other in the closed position, although their lateral expansion motion as part of the forcing planes of the above described motion of the four blade embodiment is substantially the same. In some embodiments, a single rod may be a blade and replace the potentially widest blade face of a forcing plane and still accomplish the relative upward and downward outward rotation of the top and bottom blades respectively with respect to the lateral outward motion of the left and right blades.
Alternate embodiments of the present invention arise from exclusive use of:
1. A top and bottom blade alone.
2. A top and left blade alone.
3. A left, right and top blade alone.
The novel relative motion of a left or right blade with respect to a top or bottom blade is a significant improvement of the present invention. Although many of the most important benefits of the present invention arise from the four blade embodiment, it is clear that at least part of the objects of the present invention will be obtained with use of two or three blades as described above.
The pivotal interlocking base plates with lateral motion forcing means comprise a novel arrangement accomplishment of the lateral expansion action of the present invention. It is preferable the two slotted plates pivotally attach to two solid plates. The solid plates are, on operant sides of those plates respectively, the securing surfaces for the left and right blades and, on the opposite, operator sides of those plates respectively, securing surfaces for the lateral motion forcing means. The slotted plates are, on operant sides of those plates respectively, the securing surfaces for the top and bottom blades. It is a further improvement in the base plates to provide an inside notch-out section into which forceps, probes or the like may rest and/or be secured such that other devices may be used through the generous orifice created by expansion of an orifice by the present invention. It is yet a further improvement in the base plates to provide releasable furthest expansion position means at one end of the slotted plate, such that the slotted plate of the top blade is capable of being released from pivotal attachment to the adjoining solid plate. This action permits location of forceps, probes or similar actuating, viewing or manipulating means between the edge of the orifice created with the present invention and the outside edge of the adjoining solid plate, removing its from the view- and action-blocking effects from the effective orifice created by the present invention.
The further most lateral expansion position of the four blade embodiment places the base plates of the present invention in a framing relationship for a view through the orifice expanded according to the present invention. It is preferable that the base plates will be substantially outwardly curved on an inside edge when viewed from the operator sides, i.e., the view seen by the operator of the device when looking into the expanded orifice comprises substantially a rounded opening framed by the inside edges of the base plates.
It will be understood with the present disclosure that the relative shapes, thickness, compositions and similar variables of the blades comprise a very wide range of effective aspects. Some of the effective shapes and relative configurations are disclosed below. In another embodiment of the top blade, it is shown below that a pivotal attachment may be made to effect the upward motion of the prior art vaginal speculum, such that presentation of the cervix is more effectively made.
It has been found in a prototype that a slight swiveling attachment of the shafts of the lateral motion forcing means with respect to at least one of the solid plates provides excellent expansion initiating action. Without such swiveling attachment, it has been found that initiating expansion according to the present invention is somewhat more difficult than a similar expansion of a lateral wall expander according to the prior art. It is preferred to include such a swiveling attachment between the solid plate and the lateral motion forcing means.
In a further improvement of the present invention, it has been found that a physical blade may comprise a disposable or replaceable portion and a support portion so that a single lateral motion force means and base plate assembly may be used with several blade lengths and/or be replaced between one medical examination or surgical procedure and the next. The support portion is preferably an inverted, substantially U-shaped flattened frame, whereby the tops of the inverted U-shape are secured by welding or equivalent means (as molding in the case of a plastic embodiment of the present invention) to an operant side of the base plate within the cross section area of the appropriate blade force plane. The replaceable blade preferably has a smooth, convex outer face (that face opposing an orifice edge) and two longitudinal lugs on its inner face adapted to initially engage the top of the inverted U-shape and thereby to slide securingly down the legs of the U-shape until forced against the base plate.